Electric powertrains for passenger cars are gaining interest and various solutions for such applications have been proposed during the recent years. Such powertrains may either provide purely electric drive or hybrid drive. Especially it has been suggested to provide the hybrid functionality as a separate module which is added to the existing powertrain.
Current solutions of electric powertrains are limited to one-gear transmission. A number of drawbacks are therefore associated with prior art electric driveline systems. For example, due to high torque requirements it is difficult to reduce the size of the electrical drive motor. Further, it is difficult to optimize the total efficiency of the driveline system, including the tital power consumption of the electrical drive motor, the transmission, and the power electronics.